I was expecting the 110 IS's overall performance to be pretty much identical to the 990 IS, but in fact it's quite different. It actually starts up very slightly faster, but it is very slightly slower in operation, with a single shot cycle time of 2.2 seconds and a continuous shooting mode shooting at a little less than one frame a second.
Autofocus performance is also very different. In good light the 110 IS matches the 990's speed and reliability, but in low light it is streets ahead. The IXUS 110 IS has an apparently identical AF assist lamp as its more expensive sibling, but in this case it works properly, and the camera focuses in complete darkness quickly and effectively at a range of several meters.
Thankfully one thing that remains unchanged is the outstanding performance of the optical image stabilisation system. As with the 990 IS, I was able to take shake-free hand-held shots at full telephoto zoom at shutter speeds as low as 1/10th of a second.
The performance of the built-in flash is exceptionally good, even disregarding its surprisingly small size. It is easily bright enough to fill a large living room, and the exposure system adjusts flash output, ISO and shutter speed to balance with ambient light in larger areas. The 110 IS is an excellent camera for social occasions; its wide angle lens is great for fitting in everyone sitting round a table, while the low-light focusing, excellent face detection and flash metering make sure everyone looks good.
In terms of image quality, you have to look very, very closely to spot any difference at all between the £210 camera and the £300 camera. There are differences; the 110's lens isn't quite as sharp in the centre of the frame, but it's much sharper in the corners and produces significantly less barrel distortion. It has roughly the same level of chromatic aberration, i.e. slight but noticeable. Colour reproduction, exposure and dynamic range are as good as ever.
Image noise handling is another talent the two brothers share. Shots at up to 200 ISO are pretty much noise-free, and while there are increasing signs of noise reduction at 400 and 800 ISO the image quality remains as high as possible. 1600 ISO is pixel-binned and a bit crap, but even there the colours remain accurate.
The Canon IXUS 110 IS is probably destined to be an extremely popular camera. It offers fantastic build quality, an up-to-the-minute range of features, great handling and performance, and image quality matching a camera that costs nearly half again as much. There are a few cheaper alternatives, but none that are better.